US typhoid's origin tracked to Indian subcontinent

Dr. Michael F. Lynch and colleagues studied a data on 1,902 cases of typhoid fever in U.S., between 1999 and 2006. They found that 79 percent of the total cases studied had a history of foreign travel within 30 days of falling sick.

In U.S., there has been a steady increase in cases of drug-resistant typhoid fever, federal health officials reported Tuesday.

Put together, three destinations - India (47 percent), Pakistan (10 percent) and Bangladesh (10 percent) – accounted for more than two-thirds of all travel-associated cases of typhoid fever.

The research’s findings
When the 2,016 “Typhi samples” were sent to the CDC for testing, almost 13 percent of them were resistant to antibiotics like ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole.

The typhoid infection is found mostly among young adults nearing 22 years.

Scientists from CDC said, “Typhoid fever is a rare disease in the US with approximately 300 clinical cases reported each year.

“Improvements in municipal water and sewage treatments in the U.S. resulted in dramatic declines in the incidence of and deaths from typhoid fever at the beginning of the last century. The majority of the cases in the US are now associated with foreign travel.”

Dr. Michael F Lynch, also from CDC added, “Over the last 20 years, emergence of S Typhi strains resistant to antimicrobial agents has complicated treatment of infected patients.

“The identification of nalidixic acid-resistant S Typhi (NARST) and reports of infection with S Typhi strains resistant to ciprofloxacin from typhoid-endemic areas have generated concern that strains resistant to fluroquinolones may become more prevalent.”

Lynch and colleagues concluded by saying “Reducing the burden of typhoid fever in the U.S. will require increased attention to prevention measures by travelers, including improved vaccination coverage among travelers to typhoid-endemic areas.”

“Further reductions in typhoid fever among travelers,” they added, “will depend on increased availability of safe drinking water as well as improve sanitation and food hygiene in typhoid endemic areas, measures that would go a long way toward reducing the global burden of typhoid fever.”

The study was published in the Journal of the American Medical Association on Aug. 26.

Typhoid: life-threatening fever
Typhoid fever is a potentially life-threatening bacterial infection that is usually acquired by eating contaminated food or drinking contaminated water. The illness is characterized by high fever, abdominal pain, fatigue, loss of appetite and rose-colored spots on the skin.

Every year, approximately 216,000-600,000 people are killed by the disease worldwide, infecting 21 million others annually.

In U.S. and other industrialized nations, typhoid has nearly been eliminated. Although in developing countries, this disease remains a serious health threat.